DICKCISSEL 173 



unsheathed parts of the primaries and secondaries mouse gray to 

 chaetura black narrowly margined with pallid neutral gray; wing 

 coverts olivaceous black with broad margins of cream color; edge of 

 wings, superciliary, and malar stripes light ochraceous buflF, but 

 in some younger fledglings these parts approach an orange-buff and 

 even a deep chrome in color; chin and lower breast light buff shading 

 to a lighter tint on the belly; breast and upper portion of flanks 

 chamois, but in younger specimens in which the ventral feathers 

 have just unsheathed and not been exposed to strong light the breast 

 approaches buff yellow. No birds at this stage have black streaks 

 in the breast feathers. The beak and legs are pale flesh color, but 

 these parts darken as the bird grows older. 



The dickcissel undergoes several changes by the 14th day. The 

 natal down is entirely lost; this disappears, even earlier in birds 

 that live a normal Hfe in the grass fields where it frays away more 

 quickly. The general coloration of this stage of the juvenal plumage 

 is similar to that of a bird 8 or 9 days old, but is duller in tone, with 

 none of the rich ochraceous-buff which is so conspicuous in recently 

 unsheathed feathers. This change in color is apparently due to a 

 chemical change caused by exposure either to light or to air or to 

 both. The unsheathing of the feathers in a dickcissel 14 days old 

 is so far advanced that from a casual glance it seems complete. Many 

 feathers, however, such as the primaries and secondaries still retain 

 a portion of their sheaths. Unsheathing proceeds slowly; even in 

 a bird 18 days old the outer primaries are not completely freed of 

 their envelopes. 



The dorsal plumage of an 18-day-old dickcissel is very similar in 

 color to that found in the 14-day bird described above. The ventral 

 aspect of the older bird differs as follows: Bordering the sides of 

 the throat two well-defined fuscous malar stripes extend posteriorly 

 to the breast. The sides of the chamois-colored breast are distinctly 

 streaked with fuscous. In the center of the breast, many of the 

 feathers have narrow but distinct median fuscous stripes, all of 

 which at 18 days are completely concealed from view by the over- 

 lapping tips of the feathers. A close examination of the breast 

 region reveals other similarly marked feathers in various stages of 

 development. These new feathers represent the first winter plumage, 

 destined to replace those of the juvenal phase. The breast feathers 

 in the first winter plumage differ from those of birds in the juvenal 

 stage not only in color but in their coarser texture. The transition 

 from the juvenal to the first winter plumage is not so sharply defined 

 as the change from the nuptial to the adult winter plumage, which 

 involves a complete post-nuptial molt. The post-juvenal molt 

 is only partial and occurs so gradually that it is diflBcult to determine 



